This invention relates generally to devices for detonating explosive charges in firearms. More particularly, the present invention relates to detonator assemblies for use in black powder firearms.
Although metallic cartridges and smokeless powder supplanted black powder as the preferred type of propellant in the period following the American Civil War, black powder has recently experienced a resurgence of popularity. Currently, black powder firearms are utilized for a variety of purposes including hunting, target shooting, and the reenactment of historical events.
Black powder firearms utilize as the propellant a main charge of black powder inserted into the barrel. This main charge is typically ignited by a spark or burning particles that are transmitted to the main charge though a passageway in the barrel and breech block. The method of supplying these sparks or burning particles largely depends on the degree of historical accuracy that is required for the firearm. Flintlocks and percussion caps were the predominant methods historically and generally are the predominant methods utilized today.
Flint and powder proved to be the earliest ignition mode having widespread popularity, but was subject to a number of significant problems. Principally, flint and powder ignition was subject to misfires due to loss of powder or damp powder. Percussion caps eventually provided greater reliability by eliminating the powder train.
Percussion caps are the preferred method for uses that do not require strict historical accuracy, such as hunting and target shooting. Percussion caps fit over a nipple having a throughbore. When struck by a firing pin or hammer, the percussion cap detonates and sends a flash of flame through the nipple throughbore to ignite the main powder charge. Although percussion caps are more reliable than flint, the design has experienced little technological improvement since black powder was supplanted by metallic cartridges and smokeless powder at the turn of the century. Percussion caps are relatively small and require a capper for loading and unloading. The force of detonation sometimes causes catastrophic failure of the cap causing pieces of the cap to fly off during firing. The nipple throughbore provides a passage for the escape of gases from the main powder charge. Many of the improvements to the percussion cap type of firearm have been concerned with directing the escaping gas to prevent it from becoming a hazard to the person operating the firearm.
Black powder substitutes, such as Pyrodex.TM. powder, are also now commonly used as the main powder charge. Such substitutes typically require greater thermal energy for reliable ignition than black powder. Consequently, conventional percussion caps designed for use with black powder may not provide sufficient thermal energy to reliably ignite these substitutes.